Liquid diffusion spraying mechanism

ABSTRACT

A liquid diffusion-spraying mechanism having an air motor for driving a rotary cage or slinger which carries impeller blades outwardly of the cage. A nozzle, passing through the central portion of the air motor, discharges liquid against a central baffle which deflects the liquid outwardly. Thence, the liquid passes through a peripheral screen in the cage and is broken up in small particles which are slung into the path of air created by the impeller blades. A group of the liquid diffusion-spraying mechanisms are readily arranged on a spray boom in spaced relationship, the axes of the mechanisms being parallel to each other. The air motors are arranged in series so that compressed air from a single source passes successively through the air motors for driving each of them. Valves are provided by which one or several of the mechanisms may be shut off.

United States Patent Inventor Keith Hilton Patrick Auburn, Ala.

Appl. No. 686,425

Filed Nov. 29, 1967 Patented Jan. 5, 1971 Assignee Ring Around Products,Inc.

Montgomery, Ala. a corporation of Delaware LIQUID DIFFUSION SPRAYINGMEQIIANISM 17 Claims, 5 Drawing Figs.

U.S. Cl. 239/8, 239/216, 239/224 Int. Cl A0ln 17/02 Field of Search239/7, 77, 78,l60,162,172,176, 223, 224, 222, 567, 216, 8; 261/30, 88

References Cited UNITED STATES PATENTS 2,979,269 4/1961 Bals 239/222X3,053,314 9/1962 McGillis et al 239/224X 6/1963 MacChesney 10/1966Clancy etal.

Primary Examiner-Robert B. Reeves Assistant Examiner-Norman L. Stack,Jr. Attorney-Newton, Hopkins, Jones and Onnsby ABSTRACT: A liquiddiffusion-spraying mechanism having an air motor for driving a rotarycage or slinger which carries impeller blades outwardly of the cage. Anozzle, passing through the central portion of the air motor, dischargesliquid against a central baffle which deflects the liquid outwardly.Thence, the liquid passes through a peripheral screen in the cage and isbroken up in small particles which are slung into the path of aircreated by the impeller blades.

A group of the liquid diffusion-spraying mechanisms are readily arrangedon a spray boom in spaced relationship, the axes of the mechanisms beingparallel to each other. The air motors are arranged in series so thatcompressed air from a single source passes successively through the airmotors for driving each of them. Valves are provided by which one orseveral of the mechanisms may be shutoff.

ill...

LIQUID DIFFUSION SPRAYING MECHANISM SPECIFICATION This invention relatesto a liquid diffusion-spraying mechanism and is more particularlyconcerned with an agricultural instrument which will finely divideliquids, such as liquid pesticides, and distribute the finely dividedliquid over a relatively large area. I g

In the past, various instruments have been devised for dividing liquidsand for distributing the same over relatively wide areas. Such deviceshave found wide application in creating fogs for the destruction ofvarious pests, such as mosquitoes, flies, bowl weevils, and variousother insects, fungi, and bacteria. Such instruments may also be founduseful in distributing liquid fertilizers.

The prior art devices have either distributed relatively large volumesof the liquid or have been relatively complicated and expensive. Onesuch mechanism involves the generation of high temperature gasses whichpass at high velocity through a nozzle and entrain the liquid so that'the liquid is also discharged at a high velocity from the nozzle. Ofcourse, in finely dividing the liquid and in subjecting it to relativelyhigh temperatures, there may be a breakdown of the chemicals in theliquid to be dispensed. Therefore, while such mechanisms are quiteeffective in discharging relatively large volumes of liquid, their usesmay be limited, especially when organic halogens are to be dispensedorwhere a small quantity of liquid per acre is to be dispensed.

Other types of prior art liquid-spraying mechanisms have been used, andsome have attemptedto discharge low and ultra low volumes of finelydivided liquids. Such machines, known as the Fischer and I-Iahnmachines, employ the carburetor principle using a large volume ofcompressed air at low pressure. Another type of machine is'known as theJohn Blue machine and works on the principle of blowing a large volumeof air across spray nozzles which discharge fine sprays into the blastof air.

Various liquids, such as liquid fertilizers, which may be dispensed withsuch mechanisms, are quite corrosive and, therefore, may attack themechanisms, particularly where small orifices are involved. Therefore,maintenance of such prior art devices is a major factor and is, attimes, expensive.

The present machine is different both in structure and method ofoperation from the prior art discussed above. It has a perforatedannular web which, upon rotation, functions as a diffuser and a slingerfor chopping the liquid into finely divided form and then slinging itradially outwardly for entrainment in a stream or blast of air.

Briefly described, the present invention, which is believed to obviatethe problems described above, includes a motor, preferably an air motor,which rotates the slinger or cage. The slinger or cage is a cylindricalhousing, the periphery of which isformed by a screen or perforated web.The liquid to be dispensed is passed by a central nozzle through theinterior of the motor and is discharged into the central interior of thehousing, as the housing is rotated about its axis. Circumferentiallyspaced blades project-in radial directions from the housing so that, asthe housing is rotated, the blades create an upwardly diverging conicaldischarge of air which passes over the peripheral surface of the screen.The liquid, upon being discharged into the interior of the housing,impinges upon a deflector or baffle which forms a primary diffuser andthe liquid is directed thereby outwardly, passing eventually through theperipheral screen which forms a secondary diffuser and also acts as anaccellerator which carries the liquid in an orbital path at such avelocity that the liquid, in fine droplet form, is slung by centrifugalforce radially into the air blast. By controlling the speed of rotation,the particle size of the liquid is controlled and by controlling theamount of liquid passing through the nozzle, the volume discharged peracre may be varied as desired. Indeed, quite small volumes of liquid canbe adequately entrained in quite large volumes of air and distributedover large areas.

Accordingly, it is an object of the present invention to provide aliquid diffusion spraying mechanism which is inexpensive to manufacture,durable in structure, and efficient in operation.

liquid and entrain it in a flow of air so that the liquid may bedeposited over a relatively wide area.

Another object of the present invention is to provide a liquid-sprayingmechanism which may be readily and easily arranged to be operated inconjunction with other similar mechanisms.

Another object of the present invention is to provide a liquid-sprayingassembly which consists of a series of liquidspraying mechanismsoperated in conjunction with each other to discharge liquid in finelydivided form over a relatively wide area.

Another object of the present invention is to provide a liquid-sprayingmechanism in which both the particle size and the rate at which theliquid is sprayed may be varied independently of each other. v I

Another object of the present invention is to provide a liquid-sprayingmechanism which may be readily and easily disassembled and reassembledfor cleaning purposes.

Other objects, features and advantages of the present invention willbecome apparent from the following description when taken in conjunctionwith the accompanying drawings wherein like characters of referencedesignate corresponding parts throughout the several views and wherein:

FIG. 1 is a side elevational view, partially broken away, of the liquiddiffusion-spraying mechanism of the present invention;

FIG. 2 is a cross-sectional view taken substantially along line 2-2 inFIG. 1;

FIG. 3 isa side elevational view of that portion of the mechanism shownin FIG. 2;

FIG. 4 is a vertical sectional view of the nozzle of the mechanism shownin FIG. 1;' and FIG. 5 is a schematic side elevational view, partiallybroken away, of a liquid-spraying assembly having three liquid-sprayingmechanisms, such as illustrated in. FIG. 1, arranged in spacedrelationship on a spray boom.

Referring now in detail to the embodiments chosen for the purpose ofillustrating the present invention, it being understood that in itsbroader aspects, the present invention is not limited to the exactdetails herein depicted, numeral 10 denotes, generally, a cylindricalair motor 10 having a body 11, an upper bearing housing 12, and a lowerbearing housing 13. An elongated cylindrical shaft 14 projects from theupper bearing housing 12, upwardly along the axis of the motor 10. Theshaft 14 is provided with a hollow cylindrical bore 15 whichcommunicated with the hollow interior of motor 10. The vanes (not shown)of the air motor 10 are driven by air which is introduced through intakeport 16 and is discharged through discharge port 17. The vanes (notshown) in turn, rotate shaft 14 about its axis.

The lower bearing housing 13 of motor 10 threadedly receives a hexagonalcap 18, the cap 18 being provided with the central bore aligned with thebore 15 of shaft 14. The cap 18 is internally threaded along its boreand receives the external threads of a sleeve '19 which, in turn, isinternally threaded to receive the external threads 20 on'the'shank 26of a nozzle, denoted generally by numeral 21 and seen best in FIG. 4.-In more detail, the nozzle 21 is a hollow tubular member having aflared end flange 22, at the lower end of shank 26 for rotatablyretaining a coupling 23 thereon. The coupling 23 is provided withinternal threads 24 .vhich receive the external threads of a coupling onthe end of a flexible hose, such as one of the hoses 25, seen in FIG. 5.Hoses 25 lead from a source of liquid (not shown). At the opposite endof the shank 26 from the flange 22, i.e., in the central portion ofnozzle 21, the shank 26 is integrally connected to straight cylindricalnozzle body 27 of smaller diameter than shank 26, the nozzle bodyterminating at a discharge end 28.

When the nozzle 21 is installed in the air motor 10, as illustrated inFIG. 1, it is disposed along the axis of motor and shaft 14 so that thelower end portion of the nozzle 21 protrudes below the air motor 10while the body 27 projects up through the bore of shaft 14, and projectsa short distance above the outer end 29 of the shaft 14. The diameter ofnozzle body 27 is slightly less than the diameter of bore 15 and,therefore, does not interfere with the rotation of shaft 14. It willalso be seen that the nozzle 21 is disposed concentrically within theair motor 10 and its shaft 14. The nozzle 21 does not rotate, nor doesthe body 11 or the bearing housings 12 or 13 ofthe air motor 10.

Outwardly of housing 12, the shaft 14 is provided with a collar 30having a set screw 31 for retaining collar 30 in place on shaft 14.Outwardly of the collar 30, on shaft 14, is a washer 32.

The function of shaft 14 is to rotate a hollow cylindrical cage slingeror housing, denoted generally by the numeral 33. This cylindricalslinger includes a disc-shaped or circular inner spin plate 34 and anopposed complimentary disc-shaped or circular top or outer spin plate35, which are disposed in spaced relationship, parallel to each other,being held apart by an annular diffusion member 36. The diffusion member36 is preferably a perforated web or wire screen which separates theliquid into finely divided form. Member 36 is affixed along its lowerperiphery to the outer periphery of spin plate 34 by means of braisingor the like. The upper periphery of screen 36 is fixed to the outerperiphery of an annular ring 37, the upper surface of annular ring 37abutting the peripheral lower surface area of the plate 35. Bolts 38,passing inwardly through the plate 35, and into the ring 37, removablyretain plate 35 in place on diffusion member 36. Thus, plate 35 furtherfunctions as an access plate. 1

Plate 34 is provided with a central hole through which projects shaft14, the plate 34 being received on the washer 32, in abuttingrelationship. Within the interior of the slinger 33 is the outer washer40 and the retaining nut 41. The washer 40 is received over the endportion of shaft 14 and abuts the inner surface of the spin plate 34.The nut 41 is threadedly received by the external threads at the endportion of the shaft 14. With the nut 41 tightened, the plate 34 isclamped so as to extend radially from shaft 14 and be rotated uponrotation of shaft 14.

A U-shaped strap 42 is disposed within the central portion of theslinger 33, the ends of the arms 43 and 44 of the U- shaped strap beingbraised or otherwise affixed to diametrically opposed portions of thewasher 40. The upstanding arms 43 and 44 support a transverselyextending body portion 45 parallel to and between plates 34 and 35. Thebody 45 extends transversely across the axis of the'shaft 14 and theaxis of the body 27 of nozzle 21. The body 45 is disposed in spacedrelationship beyond the end 28 of nozzle 21. Therefore, the liquiddirected through nozzle 21 is discharged from the end 28 against thebody 45 of strap 42. Thence, the liquid is directed by the body 45 ofstrap 42 outwardly toward the annular diffusion member 36.

As will be seen best in FIG. 1, the plate 34 is provided with aplurality of circumferentially equally spaced impeller or fan blades 46.These impeller blades 46 extend outwardly and downwardly from theperiphery of plate 34, being secured to the lower surface of plate 46,by bolts 47 which pass through the bases 48 of the blades 46. Thus, uponrotation of the plate 34, the blades 46 will force air upwardly, asviewed in FIG. 1, passing this air along the outer surface of thediffuser member 36, and directing the air somewhat conically upwardlyand outwardly.

The liquid which is received on the diffuser member 36 passed throughthe screen and, due to the centrifugal force created on it by beingcarried in an orbital path by the diffusion member 36, the liquid, infinelydivided form, is flung outwardly into the path of the blast of aircreated by the impeller blades 46. Thence, the liquid in droplet orfinely divided form is distributed by the conically diverging stream ofair outwardly and upwardly so that eventually the droplets fall bygravity onto a relatively large area surrounding the mechanism.

Referring specifically to FlG. 5, it will be seen that three of themechanisms illustrated in FIG. 1 may 'be arranged along a spray boom100. While various means may be employed for attaching each ofthefluid-dispensing mechanisms to the spray boom 100, I prefer to use asimple bracket, such as the brackets 101, which pass around the lowerbearing housing 13 of the motor 10. The straps 101 are retained in placeby bolts or screws 102 which pass into the boom 100. Thus, each of thefluid-dispensing mechanisms is supported with its axis disposedvertically. They are equally spaced from each other and aligned alongthe length of the boom 100. An air hose 102 leads from a source ofcompressed air to the first of a series of the mechanisms, beingconnected to its port 16. A flexible air hose 103 leads from thedischarge port 17 via a cutoff valve 104 to the part 16 of the nextadjacent mechanism. An air;

hose 105 leads through a valve 106 to the port 16 of the next subsequentair motor 10. Thus, it is seen that the air motors 10 of the adjacentmechanisms are connected in series. By such an arrangement, quiteefficient use of the compressed air ismade in driving all of the airmotors 10. Also, any one or several of the air motors may be shut off byclosing the valve 104 or 106. It will be'understood, of course, thatwhen valve- 104 or valve 106 is closed, it is open toatmosphere topermit the upstream air to discharge.

As is customary, the hoses 25 lead to a source of liquid (not shown). I

From the foregoing description, the operation of the present:

device should be apparent. In operation, liquid is introduced throughhose 25 into nozzle 21 and thence out of end 28 and against body 45. Thebody 45 of strap 42 acts as a primary diffuser or deflector whichdirects the liquid outwardly as the cage or diffusion member 33 isrotated about its axis by motor 10 and shaft 14.

When the liquid strikes the screen diffusion member 36, it is carriedwith the members 36 in an orbital path whereby the centrifugal forceurges the liquid through the member 36 and causes it to be flungoutwardly in-droplet form into the air blast created by the impellerblades 46 which arerotated with the slinger 33.

If a screen is used for the diffusion member 36, the liquid dispensed bythe mechanisms heretofore described can have a particle size of fromapproximately 10 microns to approximately 50 microns, depending on thesize of screen 36, which is employed, and depending upon the speed ofrotation of the screen 36. Furthermore, the presentmechanism isparticularly it will be understood by those skilledin the art that manyvarious types of liquids may be dispensed utilizing the equipment of thepresent invention-Pesticide in liquid form is particularly suited forbeing dispensed with the present:

mechanism. Such pesticides are conventionally applied in dilute form incombination with various nonphytotoxic' agricultural diluents, orcarriers,'in most cases, water. With the present invention, it isfeasible to reduce the amount ,of

diluent or carrier or, to do away with this carrier for mostpesticidematerials and discharge such materials in a concentrated form.

The present invention is also particularly suited for dischargingslurries, as well as true solutions, since no small nozzles and highvelocities of discharge are involved except in sofar as the rotatingscreen slinger 36 is involved.

In the preferred embodiment of the present invention, the discs 34 and35 are preferably 4 /zinches in diameter. The height of the member 36,i.e., the distance between plates 34 and 35, is approximately 3 inches.The member 36 is preferably a 40 mesh screen.

It will be obvious to those skilled in the art that many variations maybe made in the embodiments here chosen for the purpose of illustratingthe present invention without departing from the scope thereof, asdefined by the appended claims.

Iclaim:

l. A liquid diffusion-spraying head comprising, an endless diffusionmember, said diffusion member having a plurality of perforations thereinfor separating into finely divided form liquid passing therethrough,means for rotatably supporting said diffusion member, impellar means forproducing a uniform blast of air axially in one direction along theoutside surface of said diffusion member, and means for introducing aliquid into and against the inside surface of said diffusion member,said introducing means including means for passing said liquid along apath coaxial to the axis of rotation of said diffusion member and insaid one direction.

2. The structure defined in claim 1 wherein said diffusion member is anannular screen.

3. The structure defined in claim 1 wherein-said diffusion member is anannular perforated sheet, the surface of which is disposed axially withrespect to said motor.

4. The structure defined in claim 1 wherein'said means for introducingliquid against the interior surface of said diffusion member includes anozzle passing axially through and into said diffusion member fordirecting liquid centrally of screen.

5. The structure defined in claim 1 wherein said impeller means directsa flow of air over the outer surface of said diffusion member forprogressively entraining the finely divided liquid' in the flow of airand for directing the entrained liquid axially away from said diffusionmember.

6. The structure defined in claim 1 wherein said diffusion memberincludes a pair of spaced opposed parallel circular spin plates and anannular screen extending between the peripheries of said plates, one ofsaid plates being provided with a hole through which said liquid isintroduced into the interior within said plates and said diffusionmember.

7. In a liquid diffusion-spraying means as defined in claim 1 furthercharacterized in that said spraying means includes a boom-supportingstructure, supporting a plurality of spraying heads in spaced-apartrelationship.

8. The structure defined in claim I- wherein said means for directingliquid against said diffusion member includes a nozzle projectingaxially into said diffusion member.

9. The structure defined in claim.l' wherein said means for directingliquid against said diffusion member includes anozzle projecting axiallythrough said motor and terminating within the central portion of saiddiffusion member.

10. The structure defined in claim 1 wherein said impeller means isrotatable and mounted coaxially with said diffusion member.

11. In a liquid diffusion-spraying means as definedin claim 1 whereinsaid means for rotatably supporting said diffusion member comprises asupport having a motor supported thereon and wherein said diffusionmember is rotatably carried by said motor. j

12. The structure defined in claim 11 wherein said motor includes ashaft for moving said diffusion member about its axis and said diffusionmember including a spin plate mounted radially on said shaft forrotation therewith andwherein said diffusion member is a continuousscreen extending axially from and carried by said spin plate adjacentthe periphery ofsaid spin plate and against which said liquid isdirected.

13. The structure defined in claim 12 wherein saidimpeller meansincluding a lurality of impeller blades mounted on said spin plate andex ending outwardly beyond said screen for creating a flow of airdirectly over the outer periphery of said screen upon rotation of saidspin plate.

14. A liquid diffusion-spraying mechanism including a slinger having apair of spaced opposed parallel'circular inner and outer spin platesradially disposed with'respect to an axis, an annular screenconcentrically disposed with'respect to said axis and an annular ring,said screen beingsecured to the periphery of said inner spin plate andthe periphery of said ring, said outer spin plate being removablysecured to the outer surface of said ring, said inner spin plate beingprovided with a central hole, a motor, a shaft on said motor disposedalong said axis and fixed to said inner spin plate for rotating saidinner spin plate, said outer spin plate, s'aid ring and said screenabout said axis, a nozzle projecting through said shaft and terminatingwithin the central portion of said slinger and means communicating withsaid nozzle for introducing liquid into said nozzle and thence into theinterior of said slinger.

15. The structure defined in claim 14 including a liquid deflector strapin the interior of said slinger, said strap having a body portionextending approximately parallel to said plates and disposedtherebetween, said strap having a portion thereof in a position to bestruck by liquid directed by said nozzle into the interior of saidslinger.

16. A method of spraying liquid comprising the steps of; rotating anannular perforated diffusion member, passing air axially in onedirection along the outer surface of said diffusion member, directingfluid to be sprayed in said one direction and along a path coaxial tothe axis of rotation of I

1. A liquid diffusion-spraying head comprising, an endless diffusionmember, said diffusion member having a plurality of perforations thereinfor separating into finely divided form liquid passing therethrough,means for rotatably supporting said diffusion member, impellar means forproducing a uniform blast of air axially in one direction along theoutside surface of said diffusion member, and means for introducing aliquid into and against the inside surface of said diffusion member,said introducing means including means for passing said liquid along apath coaxial to the axis of rotation of said diffusion member and insaid one direction.
 2. The structure defined in claim 1 wherein saiddiffusion member is an annular screen.
 3. The structure defined in claim1 wherein said diffusion member is an annular perforated sheet, thesurface of which is disposed axially with respect to said motor.
 4. Thestructure defined in claim 1 wherein said means for introducing liquidagainst the interior surface of said diffusion member includes a nozzlepassing axially through and into said diffusion member for directingliquid centrally of screen.
 5. The structure defined in claim 1 whereinsaid impeller means directs a flow of air over the outer suRface of saiddiffusion member for progressively entraining the finely divided liquidin the flow of air and for directing the entrained liquid axially awayfrom said diffusion member.
 6. The structure defined in claim 1 whereinsaid diffusion member includes a pair of spaced opposed parallelcircular spin plates and an annular screen extending between theperipheries of said plates, one of said plates being provided with ahole through which said liquid is introduced into the interior withinsaid plates and said diffusion member.
 7. In a liquid diffusion-sprayingmeans as defined in claim 1 further characterized in that said sprayingmeans includes a boom-supporting structure, supporting a plurality ofspraying heads in spaced-apart relationship.
 8. The structure defined inclaim 1 wherein said means for directing liquid against said diffusionmember includes a nozzle projecting axially into said diffusion member.9. The structure defined in claim 1 wherein said means for directingliquid against said diffusion member includes a nozzle projectingaxially through said motor and terminating within the central portion ofsaid diffusion member.
 10. The structure defined in claim 1 wherein saidimpeller means is rotatable and mounted coaxially with said diffusionmember.
 11. In a liquid diffusion-spraying means as defined in claim 1wherein said means for rotatably supporting said diffusion membercomprises a support having a motor supported thereon and wherein saiddiffusion member is rotatably carried by said motor.
 12. The structuredefined in claim 11 wherein said motor includes a shaft for moving saiddiffusion member about its axis and said diffusion member including aspin plate mounted radially on said shaft for rotation therewith andwherein said diffusion member is a continuous screen extending axiallyfrom and carried by said spin plate adjacent the periphery of said spinplate and against which said liquid is directed.
 13. The structuredefined in claim 12 wherein said impeller means including a plurality ofimpeller blades mounted on said spin plate and extending outwardlybeyond said screen for creating a flow of air directly over the outerperiphery of said screen upon rotation of said spin plate.
 14. A liquiddiffusion-spraying mechanism including a slinger having a pair of spacedopposed parallel circular inner and outer spin plates radially disposedwith respect to an axis, an annular screen concentrically disposed withrespect to said axis and an annular ring, said screen being secured tothe periphery of said inner spin plate and the periphery of said ring,said outer spin plate being removably secured to the outer surface ofsaid ring, said inner spin plate being provided with a central hole, amotor, a shaft on said motor disposed along said axis and fixed to saidinner spin plate for rotating said inner spin plate, said outer spinplate, said ring and said screen about said axis, a nozzle projectingthrough said shaft and terminating within the central portion of saidslinger and means communicating with said nozzle for introducing liquidinto said nozzle and thence into the interior of said slinger.
 15. Thestructure defined in claim 14 including a liquid deflector strap in theinterior of said slinger, said strap having a body portion extendingapproximately parallel to said plates and disposed therebetween, saidstrap having a portion thereof in a position to be struck by liquiddirected by said nozzle into the interior of said slinger.
 16. A methodof spraying liquid comprising the steps of; rotating an annularperforated diffusion member, passing air axially in one direction alongthe outer surface of said diffusion member, directing fluid to besprayed in said one direction and along a path coaxial to the axis ofrotation of said diffusion member, and altering the direction of travelof said liquid within said diffusion member such that said liquid willbe imparted by centrifugal force outwardly through openingS in saidperforated diffusion member and into the air stream moving axially overthe surface of said diffusion member.
 17. The structure defined in claim11 wherein said motor is a fluid motor coaxially mounted with respect tosaid diffuser.